The effect of ozone therapy in root canal disinfection in primary teeth: A systematic review

Ozone therapy is a promising adjunct for root canal disinfection due to its antimicrobial action and biocompatibility. It’s efficacy versus conventional irrigants like sodium hypochlorite and chlorhexidine remains unclear. This review evaluated evidence on antimicrobial effectiveness of aqueous, gel, and gaseous ozone in root canal treatment. A thorough search of electronic databases was conducted in PubMed, Scopus, Clarivate, VHL, EBSCOhost, and Cochrane CENTRAL. Randomized clinical and in vitro studies comparing ozone’s antimicrobial action in root canals were included. Data on samples, microorganisms, ozone type, concentration, duration, comparators, and outcomes were extracted. Bias was assessed using QUIN (in vitro) and RoBDEMAT (in vivo). Due to protocol variations, only qualitative synthesis was done. Seven studies (3 in vivo, 4 in vitro) with 389 samples were analyzed. Ozone in aqueous (20–25 mg/L), gel (25 ppm), and gaseous (4 g/m 3 for 80–150 s) forms mainly targeted Enterococcus faecalis and Candida albicans. Aqueous and gaseous ozone significantly reduced bacterial counts. Gaseous ozone with sodium hypochlorite showed the greatest effect, followed by aqueous ozone and gel. One study found ozone gel less effective. Biofilm penetration limited to viscous or low-dose forms. Overall, ozone matched or exceeded sodium hypochlorite, with low to moderate bias. Ozone therapy showed strong antimicrobial action in endodontic disinfection. Aqueous and gaseous forms seem effective, biocompatible alternatives to traditional irrigants. Standardized protocols and larger trials needed to confirm and optimize its use.